Power tool

Patent metadata

Field	Value
Publication number	US-11045939-B2
Application number	US-201916256516-A
Country	US
Kind code	B2
Filing date	Jan 24, 2019
Priority date	Mar 28, 2018
Publication date	Jun 29, 2021
Grant date	Jun 29, 2021

Abstract

A power tool ( 1 ), such as a multi-tool, includes: a motor ( 21 ) extending in a front-rear direction; a motor housing ( 2 ) that houses the motor ( 21 ); a head housing ( 7 ) held forward of the motor housing ( 2 ); and an output shaft ( 60 ) protruding downward from the head housing ( 7 ). The head housing ( 7 ) may be made of a resin. In addition or in the alternative, the head housing ( 7 ) includes a lower-head housing case ( 4 ) screw fastened to an upper-head housing cover ( 5 ). In addition or in the alternative, the motor housing has a two-halved structure in which two half housings ( 2 a, 2 b ) are screw fastened together.

First claim

We claim:

1. A power tool comprising:
a motor having a rotary shaft extending in a front-rear direction;
a motor housing that houses the motor;
a head housing composed of resin and held forward of the motor housing by at least one threaded fastener inserted from a front side of the head housing into the motor housing;
an output shaft protruding downward from the head housing and extending perpendicular to the at least one threaded fastener;
a front bearing rotatably supporting a front portion of the rotary shaft of the motor and being held by the head housing;
an upper bearing rotatably supporting an upper portion of the output shaft and being held by the head housing; and
a lower bearing rotatably supporting a lower portion of the output shaft and being held by the head housing;
wherein:
the head housing has a divided structure comprising an upper half and a lower half, such that a lower-head housing case is joined to an upper-head housing cover, and
a dividing plane c between the upper and lower halves is located upward of a rotational axis line a of the motor.

2. The power tool according to claim 1 , wherein:
a rib is formed on the upper-head housing cover and mates with the lower-head housing case;
an outer ring of the lower bearing is held by the lower-head housing case; and
a tip of the rib presses against the outer ring of the lower bearing.

3. The power tool according to claim 2 , wherein the motor housing has a two-halved structure in which half housings are joined.

4. The power tool according to claim 3 , wherein the rotational axis line a of the motor is perpendicular to a pivot axis line of the output shaft.

5. The power tool according to claim 4 , further comprising:
an eccentric bearing and a lever configured to convert rotational motion of a rotary shaft of the motor into oscillating pivoting movement of the output shaft.

6. The power tool according to claim 1 , wherein the motor housing has a two-halved structure in which half housings are joined.

7. The power tool according to claim 1 , wherein the rotational axis line a of the motor is perpendicular to a pivot axis line of the output shaft.

8. The power tool according to claim 1 , further comprising:
an eccentric bearing and a lever configured to convert rotational motion of a rotary shaft of the motor into oscillating pivoting movement of the output shaft.

9. The power tool according to claim 1 , wherein the front bearing and the lower bearing are each held in the lower-head housing case and the upper bearing is held within the upper-head housing cover.

10. The power tool according to claim 1 , wherein the dividing plane c intersects the front bearing.

11. The power tool according to claim 10 , wherein the front bearing and the lower bearing are each held in the lower-head housing case and the upper bearing is held within the upper-head housing cover.

12. A power tool comprising:
a motor extending in a front-rear direction;
a motor housing that houses the motor;
a head housing held forward of the motor housing; and
an output shaft protruding downward from the head housing;
wherein:
the head housing has a divided structure that includes an upper-head housing and a lower-head housing,
the upper-head housing is fastened to the lower-head housing by at least one threaded fastener that extends through at least a portion of the lower-head housing and into the upper-head housing such that a head of the at least one threaded fastener is seated on or in the lower-head housing;
a dividing plane c between the upper-head housing and the lower-head housing is located upward of a rotational axis line a of the motor;
a rib is formed on the upper-head housing and mates with the lower-head housing;
a tip side of the output shaft is rotatably supported by the lower-head housing via a bearing;
an outer ring of the bearing is held by the lower-head housing; and
a tip of the rib presses against the outer ring of the bearing.

13. The power tool according to claim 12 , wherein the motor housing has a two-halved structure in which half housings are joined.

14. A power tool comprising:
a motor having a rotary shaft extending in a front-rear direction;
a motor housing that houses the motor;
a head housing including an upper-head housing connected with a lower-head housing;
an output shaft protruding downward from the lower-head housing;
a front bearing rotatably supporting a front portion of the rotary shaft of the motor and disposed within the lower-head housing;
an upper bearing rotatably supporting an upper portion of the output shaft and being disposed within the upper-head housing; and
a lower bearing rotatably supporting a lower portion of the output shaft and being disposed within the lower-head housing;
wherein:
the lower-head housing has an inner circumferential surface forming a cylindrical bore and
the upper-head housing has a circular-cylindrical-shaped rib protruding downwardly from a remainder of the upper-head housing beneath the upper bearing and disposed within the cylindrical bore of the lower-head housing.

15. The power tool according to claim 14 , wherein a base-end side diameter of an outer circumferential surface of the rib is equal to or larger than an upper-side inner diameter of the inner circumferential surface of the lower-head housing such that the rib mates with the lower-head housing.

Assignees

• Makita Corp

Inventors

• Kotsuji Takafumi
• Mizutani Akira

Classifications

• B26D1/30

  with limited pivotal movement to effect cut · CPC title

• B25F5/02 Primary

  Construction of casings, bodies or handles {(B25F5/006, B25F5/008 take precedence)} · CPC title

• B27B19/006

  with oscillating saw blades; Hand saws with oscillating saw blades · CPC title

• B25D16/006

  Mode changers; Mechanisms connected thereto · CPC title

• B25B23/141

  Mechanical overload release couplings · CPC title